src/main/java/com/dino/scrum/sysmag/controller/ProductController.java

@@ -8,6 +8,7 @@ import com.dino.scrum.sysmag.validationGroup.UpdateGroup;
 import com.dino.scrum.sysmag.validator.QuantityChangeValidator;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.domain.Pageable;
+import org.springframework.data.web.PageableDefault;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
@@ -38,8 +39,14 @@ public class ProductController {
     }
 
     @GetMapping(value = "/get-all")
-    public Iterable<Product> getAll(Pageable pageable) {
+    public Iterable<Product> getAll(@PageableDefault(size = Integer.MAX_VALUE) Pageable pageable) {
-        return productService.getAll(pageable);
+        System.out.println(pageable.getPageSize());
+
+        try {
+            return productService.getAll(pageable);
+        } catch (Exception e) {
+            throw new ResponseStatusException(HttpStatus.BAD_REQUEST, e.toString());
+        }
     }
 
     @GetMapping(value = "/get-price-of-all")

src/main/java/com/dino/scrum/sysmag/service/ProductService.java

@@ -2,15 +2,15 @@ package com.dino.scrum.sysmag.service;
 
 import com.dino.scrum.sysmag.model.Product;
 import com.dino.scrum.sysmag.model.dto.QuantityChange;
+import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
-import org.springframework.data.domain.Slice;
 
 /**
  * Created by prgres on 2019-01-12.
  */
 
 public interface ProductService {
-    Slice<Product> getAll(Pageable pageable);
+    Page<Product> getAll(Pageable pageable) throws Exception;
 
     Product changeQuantity(QuantityChange quantityChange) throws Exception;
 
@@ -20,6 +20,8 @@ public interface ProductService {
 
     Product update(Product product, long id) throws Exception;
 
+    long count();
+
     float getPriceOfAll();
 
     void delete(long id) throws Exception;

src/main/java/com/dino/scrum/sysmag/service/ProductServiceImpl.java

@@ -5,9 +5,9 @@ import com.dino.scrum.sysmag.model.dto.QuantityChange;
 import com.dino.scrum.sysmag.repository.ProductRepository;
 import com.dino.scrum.sysmag.validator.ProductValidator;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
-import org.springframework.data.domain.Slice;
 import org.springframework.data.domain.Sort;
 import org.springframework.stereotype.Service;
 
@@ -33,16 +33,23 @@ public class ProductServiceImpl implements ProductService {
     }
 
     @Override
-    public Slice<Product> getAll(Pageable pageable) {
+    public Page<Product> getAll(Pageable pageable) throws Exception {
+        System.out.println("pagenumber: " + pageable.getPageNumber() + " pageSize: " + pageable.getPageSize() + " sort: " + pageable.getSort());
+
         if (pageable.getSort().isUnsorted()) {
             pageable = PageRequest.of(pageable.getPageNumber(), pageable.getPageSize(), new Sort(Sort.Direction.ASC, "id"));
         }
-        return productRepository.findAll(pageable);
+
+        Page<Product> productSlice = productRepository.findAll(pageable);
+
+        productValidator.checkIfPageIsOutOfBound(productSlice.getTotalPages(), pageable.getPageNumber());
+
+        return productSlice;
     }
 
     @Override
     public Product changeQuantity(QuantityChange quantityChange) throws Exception {
-        productValidator.checkIfExists(quantityChange.getId());
+        productValidator.checkIfNotExists(quantityChange.getId());
 
         productRepository.save(
                 productRepository.findById(quantityChange.getId())
@@ -54,7 +61,7 @@ public class ProductServiceImpl implements ProductService {
 
     @Override
     public Product getById(Long id) throws Exception {
-        productValidator.checkIfExists(id);
+        productValidator.checkIfNotExists(id);
         return productRepository.findById(id.longValue());
     }
 
@@ -73,13 +80,13 @@ public class ProductServiceImpl implements ProductService {
 
     @Override
     public Product add(Product product) throws Exception {
-        productValidator.checkIfExists(product.getName());
+        productValidator.checkIfNotExists(product.getName());
         return productRepository.save(product);
     }
 
     @Override
     public Product update(Product productReceived, long id) throws Exception {
-        productValidator.checkIfExists(productReceived.getId());
+        productValidator.checkIfNotExists(productReceived.getId());
 
         Product productToChange = productRepository.findById(id);
 
@@ -103,9 +110,14 @@ public class ProductServiceImpl implements ProductService {
         return productRepository.findById(productToChange.getId().longValue());
     }
 
+    @Override
+    public long count() {
+        return productRepository.count();
+    }
+
     @Override
     public void delete(long id) throws Exception {
-        productValidator.checkIfExists(id);
+        productValidator.checkIfNotExists(id);
         productRepository.deleteById(id);
     }
 }

src/main/java/com/dino/scrum/sysmag/validator/ProductValidator.java

@@ -26,14 +26,23 @@ public class ProductValidator {
         return productRepository.existsByName(name);
     }
 
-    public void checkIfExists(long id) throws Exception {
+    private boolean ifRequestPageInLimit(int limit, int requestPage) {
+        return requestPage < limit;
+    }
+
+    public void checkIfNotExists(long id) throws Exception {
         if (!existsById(id))
             throw new Exception("Product with id: " + id + " not found");
         System.out.println(id + " exists");
     }
 
-    public void checkIfExists(String name) throws Exception {
+    public void checkIfNotExists(String name) throws Exception {
-        if (!existsByName(name))
+        if (existsByName(name))
             throw new Exception("Product " + name + " already exists");
     }
+
+    public void checkIfPageIsOutOfBound(int totalPages, int requestPage) throws Exception {
+        if (ifRequestPageInLimit(requestPage, totalPages))
+            throw new Exception("Page " + requestPage + " is out of the total pages number.");
+    }
 }